Salivary proteins modulate Candida albicans virulence and may prevent oropharingeal candidiasis.

Oral candidiasis can be presented in different ways due to the virulence factors of its etiology such as Candida albicans that have developed an effective set of these factors that are able to improve its pathogenesis. The role of salivary immunological components in the development of candidiasis can provide insights for the development of new methodologies aiming to control this disease. The aim of this study was to evaluate the antifungal activity of two salivary components, histatin 5 and lactoferrin on C.

Anti-Leishmania amazonensis activity of the marine sponge Dercitus (Stoeba) latex (Porifera) from São Pedro and São Paulo Archipelago, Pernambuco, Brazil.

The search for new therapeutic strategies for leishmaniasis treatment is essential due to the side effects of available drugs and the increasing incidence of resistance to them. Marine sponges use chemical compounds as a defense mechanism, and several of them present interesting pharmacological properties. The aim of this study was to evaluate the in vitro activity of the aqueous extract of the marine sponge Dercitus (Stoeba) latex against Leishmania amazonensis.

Lopinavir and Nelfinavir Induce the Accumulation of Crystalloid Lipid Inclusions within the Reservosomes of and Inhibit Both Aspartyl-Type Peptidase and Cruzipain Activities Detected in These Crucial Organelles.

Several research groups have explored the repositioning of human immunodeficiency virus aspartyl peptidase inhibitors (HIV-PIs) on opportunistic infections caused by bacteria, fungi and protozoa. In , HIV-PIs have a high impact on parasite viability, and one of the main alterations promoted by this treatment is the imbalance in the parasite's lipid metabolism. However, the reasons behind this phenomenon are unknown.

Endocytosis and Exocytosis in Are Modulated by Bromoenol Lactone.

In the protozoan pathogen , endocytosis, and exocytosis occur mainly in the small area of the flagellar pocket membrane, which makes this parasite an interesting model of strikingly polarized internalization and secretion. Moreover, little is known about vesicle recognition and fusion mechanisms, which are essential for both endo/exocytosis in this parasite. In other cell types, vesicle fusion events require the activity of phospholipase A (PLA), including Ca-independent iPLA and soluble, Ca-dependent sPLA.

: cell surface dynamics in trypomastigotes of different strains.

Capping and shedding of ectodomains in Trypanosoma cruzi may be triggered by different ligands. Here, we analysed the mobility and shedding of cell surface components of living trypomastigotes of the Y strain and the CL Brener clone in the presence of poly-L-lysine, cationized ferritin (CF) and Concanavalin A (Con A). Poly-L-lysine and CF caused intense shedding in Y strain parasites.

LPL protein in Chronic Lymphocytic Leukaemia have different origins in Mutated and Unmutated patients. Advances for a new prognostic marker in CLL.

Lipoprotein lipase (LPL) mRNA expression in chronic lymphocytic leukaemia (CLL) is associated with an unmutated immunoglobulin profile and poor clinical outcome. We evaluated the subcellular localization of LPL protein in CLL cells that did or did not express LPL mRNA. Our results show that LPL protein is differently located in CLL cells depending on whether it is incorporated from the extracellular medium in mutated CLL or generated de novo by leukaemic cells of unmutated patients.

The in vitro antileishmanial activity of essential oil from Aloysia gratissima and guaiol, its major sesquiterpene against Leishmania amazonensis.

Leishmaniases is a tropical disease caused by protozoa of the genus Leishmania for which the current treatment is expensive, besides increasing reports of parasite resistance. This study investigated the anti-Leishmania amazonensis activity of the essential oil from Aloysia gratissima (AgEO) and guaiol, the major sesquiterpene constituent in the oil. Our results showed that AgEO killed promastigotes and intracellular amastigotes at an IC50 of 25 and 0·16 µg mL-1, respectively, while guaiol killed amastigotes at an IC50 of 0·01 µg mL-1.

Triatoma infestans relies on salivary lysophosphatidylcholine to enhance Trypanosoma cruzi transmission.

Triatoma infestans is a mandatory haematophagous vector of Chagas disease in Brazil. Despite a large number of studies on the anti-haemostatic molecules present in its saliva, the role of its salivary components on parasite transmission is poorly understood. Here, we show that the bioactive lipid molecule, lysophosphatidylcholine (LPC), is present in the salivary gland of T.

Hyicin 4244, the first sactibiotic described in staphylococci, exhibits an anti-staphylococcal biofilm activity.

Hyicin 4244 is a small antimicrobial peptide with a broad spectrum of activity that was found in the culture supernatant of Staphylococcus hyicus 4244, the genome of which was then sequenced. The bacteriocin gene cluster (hyiSABCDEFG) was mined from its single chromosome and exhibited a genetic organization similar to that of subtilosin A. All genes involved in hyicin 4244 biosynthesis proved to be transcribed and encode proteins that share at least 42% similarity to proteins encoded by the subtilosin A gene cluster.

In vitro anti-MRSA activity of Couroupita guianensis extract and its component Tryptanthrin.

Couroupita guianensis is known in Brazil as 'Abricó-de-Macaco' and it has some attributes such as: antihypertensive, analgesic and anti-inflammatory activities. This study evaluated the antimicrobial activity of ethanolic extract and fractions of C. guianensis flowers and isolation of bioactive component.

Antiproliferative and ultrastructural effects of phenethylamine derivatives on promastigotes and amastigotes of Leishmania (Leishmania) infantum chagasi.

Leishmania (Leishmania) infantum chagasi is one of the agents that cause visceral leishmaniasis. This disease occurs more frequently in third world countries, such as Brazil. The treatment is arduous, and is dependent on just a few drugs like the antimonial derivatives and amphotericin B.

Phylogenetic and morphological characterization of trypanosomes from Brazilian armoured catfishes and leeches reveal high species diversity, mixed infections and a new fish trypanosome species.

Background: Several Trypanosoma species transmitted by leeches infect marine and freshwater fish worldwide. To date, all South American fish trypanosome species identified have been based on unreliable morphological parameters. We recently isolated and cultured trypanosomes from the Brazilian armoured catfishes Hypostomus luetkeni and H.

Phenotypic and genotypic characterization of biofilm formation in Staphylococcus haemolyticus.

Staphylococcus haemolyticus is one of the most frequently isolated coagulase-negative staphylococci. The ability to produce biofilm has contributed to its emergence as a nosocomial pathogen. In this study, some growth conditions were tested to determine their influence on biofilm formation.

Crovirin, a snake venom cysteine-rich secretory protein (CRISP) with promising activity against Trypanosomes and Leishmania.

Background: The neglected human diseases caused by trypanosomatids are currently treated with toxic therapy with limited efficacy. In search for novel anti-trypanosomatid agents, we showed previously that the Crotalus viridis viridis (Cvv) snake venom was active against infective forms of Trypanosoma cruzi. Here, we describe the purification of crovirin, a cysteine-rich secretory protein (CRISP) from Cvv venom with promising activity against trypanosomes and Leishmania.

Transovum transmission of trypanosomatid cysts in the Milkweed bug, Oncopeltus fasciatus.

Leptomonas wallacei is a trypanosomatid that develops promastigotes and cystic forms in the gut of the hemipteran insect Oncopeltus fasciatus. Insect trypanosomatids are thought to be solely transmitted from one host to another through the ingestion of parasite-contaminated feces. However, here we show that L.

Structural and functional analysis of a platelet-activating lysophosphatidylcholine of Trypanosoma cruzi.

Background: Trypanosoma cruzi is the causative agent of the life-threatening Chagas disease, in which increased platelet aggregation related to myocarditis is observed. Platelet-activating factor (PAF) is a potent intercellular lipid mediator and second messenger that exerts its activity through a PAF-specific receptor (PAFR). Previous data from our group suggested that T.

Golgi UDP-GlcNAc:polypeptide O-α-N-Acetyl-d-glucosaminyltransferase 2 (TcOGNT2) regulates trypomastigote production and function in Trypanosoma cruzi.

All life cycle stages of the protozoan parasite Trypanosoma cruzi are enveloped by mucin-like glycoproteins which, despite major changes in their polypeptide cores, are extensively and similarly O-glycosylated. O-Glycan biosynthesis is initiated by the addition of αGlcNAc to Thr in a reaction catalyzed by Golgi UDP-GlcNAc:polypeptide O-α-N-acetyl-d-glucosaminyltransferases (ppαGlcNAcTs), which are encoded by TcOGNT1 and TcOGNT2. We now directly show that TcOGNT2 is associated with the Golgi apparatus of the epimastigote stage and is markedly downregulated in both differentiated metacyclic trypomastigotes (MCTs) and cell culture-derived trypomastigotes (TCTs).

Effect of the secretory leucocyte proteinase inhibitor (SLPI) on Candida albicans biological processes: a therapeutic alternative?

Objectives: The aim of this study was to evaluate the effect of SLPI on the growth and biological processes of Candida albicans.

Methods: Two C. albicans strains were used in this study, a clinical isolate resistant to fluconazole (PRI) and a reference strain ATCC 24433.

Trypanosoma cruzi-secreted vesicles have acid and alkaline phosphatase activities capable of increasing parasite adhesion and infection.

Trypanosoma cruzi virulence factors include molecules expressed on the cell surface as well as those secreted or shed into the extracellular medium. Phosphatase activities modulate different aspects of T. cruzi infection, although no studies to date addressed the presence and activity of phosphatases in vesicles secreted by this parasite.

Gene expression changes induced by Trypanosoma cruzi shed microvesicles in mammalian host cells: relevance of tRNA-derived halves.

At present, noncoding small RNAs are recognized as key players in novel forms of posttranscriptional gene regulation in most eukaryotes. However, canonical small RNA pathways seem to be lost or excessively simplified in some unicellular organisms including Trypanosoma cruzi which lack functional RNAi pathways. Recently, we reported the presence of alternate small RNA pathways in T.

Isolation and in vitro maintenance of trypanosomes from naturally infected and commercially important Brazilian fish.

Fish trypanosomes are widely distributed in commercially important fish, with high prevalence in some Brazilian species. This study provides the first record of the isolation and in vitro maintenance of trypanosomes from Brazilian fish. We produced 49 trypanosome isolates from naturally infected catfish (Hypostomus affinis and Hypostomus luetkeni), using 9 different culture media (out of 31 tested).

The calpain inhibitor MDL28170 induces the expression of apoptotic markers in Leishmania amazonensis promastigotes.

Background: Human cutaneous leishmaniasis is caused by distinct species, including Leishmania amazonensis. Treatment of cutaneous leishmaniasis is far from satisfactory due to increases in drug resistance and relapses, and toxicity of compounds to the host. As a consequence for this situation, the development of new leishmanicidal drugs and the search of new targets in the parasite biology are important goals.

Extracellular vesicles shed by Trypanosoma cruzi are linked to small RNA pathways, life cycle regulation, and susceptibility to infection of mammalian cells.

The protozoan parasite Trypanosoma cruzi has a complex life cycle characterized by intracellular and extracellular forms alternating between invertebrate and mammals. To cope with these changing environments, T. cruzi undergoes rapid changes in gene expression, which are achieved essentially at the posttranscriptional level.

The immune response of hemocytes of the insect Oncopeltus fasciatus against the flagellate Phytomonas serpens.

The genus Phytomonas includes parasites that are etiological agents of important plant diseases, especially in Central and South America. These parasites are transmitted to plants via the bite of an infected phytophagous hemipteran. Despite the economic impact of these parasites, many basic questions regarding the genus Phytomonas remain unanswered, such as the mechanism by which the parasites cope with the immune response of the insect vector.

Melittin peptide kills Trypanosoma cruzi parasites by inducing different cell death pathways.

Antimicrobial peptides (AMPs) are components of the innate immune response that represent desirable alternatives to conventional pharmaceuticals, as they have a fast mode of action, a low likelihood of resistance development and can act in conjunction with existing drug regimens. AMPs exhibit strong inhibitory activity against both Gram-positive and Gram-negative bacteria, fungi, viruses, metazoans and other parasites, such as the protozoan Leishmania. Melittin is a naturally occurring AMP, which comprises 40-50% of the dry weight of Apis mellifera venom.